void sendTextFrame(WebSocket& ws, const std::string& s)
{
ws.sendFrame(s.data(), s.size());
}
int main()
{
AutoPtr<XMLConfiguration> pConf(new XMLConfiguration("settings.xml")); // instantiating the XMLConfiguration and reading from setting.xml
char buffer[2048];
memset(buffer, 0, sizeof buffer);
int flags;
int n;
string payload;
string out;
int msg_cnt = 0;
pthread_t fifoReadThread; //indivudual thread for fifo so it doesn't block other stuff
int iret1 = pthread_create(&fifoReadThread, NULL, CreatePiSocketFifo, NULL);
//variables to be set in xml config file //
string signalr_service_url = pConf->getString("signalr_url");
string signalr_url_endpoint = pConf->getString("signalr_url_endpoint");
int signalr_service_port = pConf->getInt("signalr_port");
int timeout_seconds = pConf->getInt("timeout");
string api_endpoint_url = pConf->getString("api_endpoint_url"); // ""
//pipe_from_main = pConf->getString("pipe_from_main");
//string pipe_from_socket = pConf->getString("pipe_from_socket");
//--------------------------------------//
//cout << endl << "=============================================================" << endl;
//cout << "api_endpoint_url -> " << api_endpoint_url << endl;
//cout << "signalr_url_endpoint -> " << signalr_url_endpoint << endl;
//cout << "signalr_service_port -> " << signalr_service_port << endl;
//cout << "timeout_seconds -> " << timeout_seconds << endl;
//cout << "api_endpoint_url -> " << api_endpoint_url << endl;
//cout << "pipe_from_main -> " << pipe_from_main;
//cout << endl << "=============================================================" << endl << endl;
//cout << "Opening pipe: " << pipe_from_main << endl;
//fd = open(pipe_from_main.c_str(), O_WRONLY); // open pipe as readonly
//write(fd, "Hello World", sizeof("Hello World"));
//close(fd);
conn: //label for the goto's in the catches
try{
time_t seconds_past_epoch = time(0);
cout << "STARTING " << endl;
char port[100];
char id[100];
snprintf(port, sizeof(port), "%d", signalr_service_port); // converting int variables to char[]
snprintf(id, sizeof(id), "%ld", (seconds_past_epoch * 1000)); // converting int variables to char[]
string my_mac = getMACC(); //Get the mac address
//compose the URI for getting the token
URI uri("http://" + signalr_service_url + ":" + port + "/" + signalr_url_endpoint + "/negotiate?_" + id + "&UID=" + my_mac);
HTTPClientSession session(uri.getHost(), uri.getPort()); // instantiating a client session
//if there is a network problem between Pi and SignalR everything will break and the catch will point back to the goto label
//we set this in order to a lower minimise the retry period thus the downtime
session.setTimeout(timeout_seconds * 1e+6); // time in microseconds;
string path(uri.getPathAndQuery());
// send the request
HTTPRequest req(HTTPRequest::HTTP_GET, path, HTTPMessage::HTTP_1_1);
session.sendRequest(req);
StringTokenizer tokenizer(session.socket().address().toString(), ":", StringTokenizer::TOK_TRIM); // get the request originating address:ip from the session socket initiated by HTPP; tokenize it for IP extraction
//string my_mac = getMAC((tokenizer[0]).c_str()); // call IP to MAC converter
// get response
HTTPResponse res;
istream& is = session.receiveResponse(res); // stream the request
cout << res.getStatus() << " " << res.getReason() << endl; // get the status code of the transaction
// convert the istream to sting for further processing
istreambuf_iterator<char> eos;
string s(istreambuf_iterator<char>(is), eos);
const char * cc = s.c_str();
// instantiate a rapidjson document and fill it up with the response of the negotiation request
rapidjson::Document document;
document.Parse<0>(cc);
string token = document["ConnectionToken"].GetString(); // parse the response and get the connectionToken
//=============================================
//connect to signarR using the connectionToken got previously
HTTPClientSession cs(signalr_service_url, signalr_service_port); // instantiate simple webclient
string what = "/" + signalr_url_endpoint + "/connect?transport=webSockets&connectionToken=" + urlencode(token) + "&UID=" + my_mac + "&connectionData=%5B%7B%22name%22%3A%22myhub%22%7D%5D&tid=10"; // compose the request string
HTTPRequest request(HTTPRequest::HTTP_GET, what, "HTTP/1.1"); // the protocol MUST be HTTP/1.1, as described in RFC6455; else the UPGRADE to websocket request will fail
request.set("Host", signalr_service_url); // specify the Host header to be sent
HTTPResponse response; // instantiate a http response
cout << response.getStatus() << " " << response.getReason() << endl;
WebSocket * ws = new WebSocket(cs, request, response); // instantiate a WebSocket transaction to the 'cs' session, sending the 'request' and storing the 'response'
//sample of a message to be sent
payload = "{\"H\":\"myhub\",\"M\":\"Send\",\"A\":[\"" + my_mac + "\",\"invoked from " + replaceInPlace(my_mac, std::string(":"), std::string("-")) + " client\"],\"I\":0}";
// cout << endl << payload << endl ;
ws->sendFrame(payload.data(), payload.size(), WebSocket::FRAME_TEXT); // send the message to signalR using the payload and setting the type of frame to be sent as FRAME_TEXT
flags = 1;
// starting the receiving loop
while( (flags & WebSocket::FRAME_OP_BITMASK) != WebSocket::FRAME_OP_CLOSE ) // while websocket session open
{
n = ws->receiveFrame(buffer, sizeof(buffer), flags); // n is the received frame
// flags store the response flags of the frame
// 129 = single frame response
// 1 = start of multi-frame response
// 0 = continuation frame of a multi-frame response
// 128 = FIN frame os a multi-frame response
// signalR send data in JSON format, and it send empty messages (empty json document) on a regular basis
if( (n != 2) && flags !=1 ) // filter out empty jsons and multiframe responses (multiframe will be treated further on)
{
cout << "RCV[" << msg_cnt << "]=> " << buffer << " ===== " << unsigned(flags) << endl;
}
if(flags == 1){ // if I get a start frame of a multi-frame response means that I am getting something usefull from signalR
string str(buffer);
out += str;
// due to flag == 1, we are expecting several frames, until we got flag == 128
do{
n = ws->receiveFrame(buffer, sizeof(buffer), flags);
string str(buffer);
out += str; // we add the next frame/frames to the out variable, to construct the whole JSON message
str = "";
memset(buffer, 0, sizeof buffer); // be sure to empty the buffer to don't end up with junk
}while(flags != 128);
cout << endl << "=> " << out << endl;
//not as we got a valid response from signalR endpoint, lets process it
//convert the out variable and pass is as a Document to the JSON parser
const char * c = out.c_str();
rapidjson::Document document;
document.Parse<0>(c);
out = document["M"][rapidjson::SizeType(0)]["A"][rapidjson::SizeType(1)].GetString(); // get out only the actual sent message from the response message
SendMessageToMain(out.c_str());
cout << "Msg Received";
message_action(api_endpoint_url,out); // do something with the message in the message_action function
out = "";
}
msg_cnt++;
memset(buffer, 0, sizeof buffer); // we always cleanup
}
ws->shutdown();
}
// if something goes wrong with the connection, we try to recover
catch (WebSocketException& exc0)
{
cout <<"WebSocketException "<< exc0.displayText() << endl;
}
catch (Poco::TimeoutException& exc1) // handle webclient errors
{
goto conn; // lets try again from the top
cout <<"TimeoutException "<< exc1.displayText() << endl;
// return 1;
}
catch (ConnectionResetException& exc) // handle connec errors
{
goto conn; // lets try again from the top
cout << "!!!ConnectionResetException:" << exc.displayText() << endl;
// return 1;
}
cout << strerror(errno) << endl;
return 0;
}